m4/longlong.m4

   1 #serial 3
   2
   3 dnl From Paul Eggert.
   4
   5 AC_DEFUN([jm_AC_TYPE_UNSIGNED_LONG_LONG],
   6 [
   7   AC_CACHE_CHECK([for unsigned long long], ac_cv_type_unsigned_long_long,
   8   [AC_TRY_LINK([unsigned long long ull = 1; int i = 63;],
   9     [unsigned long long ullmax = (unsigned long long) -1;
  10      return ull << i | ull >> i | ullmax / ull | ullmax % ull;],
  11     ac_cv_type_unsigned_long_long=yes,
  12     ac_cv_type_unsigned_long_long=no)])
  13   if test $ac_cv_type_unsigned_long_long = yes; then
  14     AC_DEFINE(HAVE_UNSIGNED_LONG_LONG, 1,
  15       [Define if you have the unsigned long long type.])
  16   fi
  17 ])